Device for producing a spring manometer measuring system

ABSTRACT

A spring manometer measuring system that includes a deviation detector spring in the manometer connected to an indicator by a tie rod, and the spring is subjected to a reference pressure for spring deflection measurement before producing the bearing for the tie rod.

This is a division of application Ser. No. 854,645 filed Nov. 25, 1977,now U.S. Pat. No. 4,148,123.

This invention relates to a spring manometer measuring system consistingof an indicator, a spring serving as a deviation detector and a tie rodconnecting the indicator to the spring, as well as a device forproducing such a spring manometer measuring system and a tube springmanometer.

The inventive method and device are basically applicable to theproduction of measuring systems in which an at least approximatelyrectilinear movement of a deviation detector must be transmitted to anindicator. In the following the invention will be explained withreference to the production of a measuring system for a tube springmanometer without restricting the invention to the production of such ameasuring system.

The measuring system of a tube spring manometer normally includes adeviation or deflection detector which is designed as a tube spring andwhich is secured to a deviation detector support, an indicator whichconverts the movement of the end of a spring into a movement suitablefor display or conversion of the measured value, and a connecting memberwhich connects the end of the spring to the indicator. In the case ofpointer manometers, the indicator is a pointer train. A pointer can beplaced on the pointer shaft of such a pointer train. A pinion on thepointer shaft engages directly or indirectly a toothed segment pivotallymounted on a segment axis. This toothed segment also includes a segmentlever which articulates with the tie rod at a point of articulation. Theother end of said tie rod articulates at an end point with an end piecesecured to the end of the spring. The deflection of the end of thespring can thus be converted into a rotary movement of the pointer whoseposition can be read off a scale or dial.

Such a measuring system is produced conventionally in the followingmanner. The tube spring is rigidly connected to the deviation detectorsupport on the one hand and on the other hand to the end piece which hasa hole forming the end point for insertion of the tie rod. The pointertrain is manufactured separately and the segment lever thereof isprovided with a hole forming the point of articulation even before thepointer train is assembled in the measuring system. The pointer trainand the deviation detector support which supports the tube spring arerigidly interconnected, whereupon the tie rod is mounted, for example,with the aid of rivets inserted through the two holes and the two endsof the tie rod. The dial, which also belongs to the manometer, can beaffixed to the deviation detector support together with the pointertrain, for example.

When subjected to a pressure, such a measuring system is supposed toindicate this pressure within permissible tolerances. The pointerdeflection beginning at zero and corresponding to the nominal pressureor the final scale value is termed the span. Furthermore, the indicationshould be linear within permissible tolerances, i.e. in the case offractions of the nominal pressure, the pointer deflection shouldcorrespond to these fractions. In the case of the afore-describedproduction of measuring systems, both the positions of the holes for theend point and point of articulation as well as the deflection of the endof the spring when subjected to the nominal pressure, here designated asthe spring excursion, are subject to certain fluctuations due to themanufacturing tolerances from measuring system to measuring system whichaffect the span and linearity. An adjustment of each and every measuringsystem is therefore necessary if the permissible display tolerances areto be observed.

The span depends substantially on the lever arm, i.e. the distance ofthe point of articulation from the segment axis, the spring excursionand the end point position, i.e. the distance from the end point to theimaginary pivot point of the end or to the end of the spring. Thelinearity depends substantially on the pivot angle, i.e. the anglebetween the straight line extending from the segment axis to the pointof articulation and the straight line extending from the point ofarticulation to the end point. The geometric and kinematic relationsbetween these quantities are known.

Adjustment is conventionally effected in such a manner that the springis subjected to a specific reference pressure and the deflection of thespring is measured at the same time. The deflection is measured byreading off the pressure indicated by the measuring system which isalready provided with a pointer. If the indicated span is outsidepermissible tolerances, the lever arm or the end point position ischanged manually. This change can be made by bending a hook formed onthe segment lever or on the end piece, the hole for the point ofarticulation or the end point being located at the free end of saidhook. Alternatively, this change can also be made by displacing thepoint of articulation or the end point in an elongated hole in thesegment lever or end piece. The linearity, i.e. the pivot angle, isadjusted by manually changing the length of the tie rod or the positionof the pivot point or the end point in a described manner (cf. theperiodical "Die Technik", Vol. 3, No. 1, January 1948, pages 28 and 29).Alternatively, it is possible to adjust the pivot angle by turning theindicator in the manometer housing. It is obvious that every adjustmentof the span necessarily changes the linearity and that every adjustmentin linearity in turn influences the span so that as a rule the span andlinearity have to be adjusted several times in an alternating fashionuntil the desired display tolerances are attained. It is self-evidentthat the conventional adjustment procedure is thus a time-consuming andexpensive operation.

The necessity of being able to adjust a measuring system in theafore-mentioned manner is accompanied by yet other limitations and thusdrawbacks during the production of the measuring system.

In order to prevent the adjustment from becoming too expensive,relatively low tolerances must be observed in a conventional manometerwhen connecting the tube spring with the deviation detector support onthe one hand and with the end piece on the other hand in which the holefor the end point has already been formed. This of course increases themanufacturing expenses.

In order for the lever arm to be changed during adjustment, at least onesection of the segment lever must be plastically deformable or it musthave an elongated hole.

For this reason the segment lever must be made of metal, which iscostly, or it must have at least a complicated shape which alsoincreases the manufacturing expenses.

Conventional manometers feature zero suppression so that a definedinitial position is given for the pointer on the one hand and so that,on the other hand, the pointer train does not demesh when the spring issubjected to a sub-pressure, i.e. so that the toothed segment and thepinion do not disengage. This zero suppression is embodied by a stop pinon the dial whose manufacture and assembly incur expenses and which canalso cause damage to other dials during storage. Replacing this stop pinby a non-adjustable stop in the pointer train has hitherto not beenpossible, since the zero position of the pointer train elements is notestablished until after adjustment. On the contrary, the position of thepointer train elements must be variable in order to effect adjustment.

The object of the invention is to provide a method for producing aspring manometer measuring system which makes it possible to reduce theexpenses incurred during conventional adjustment.

In accordance with a first embodiment of the invention, this object isaccomplished by a method for producing a spring manometer measuringsystem consisting of an indicator, a spring serving as a deviationdetector and a tie rod connecting the indicator to the spring, a bearingdefining an end point being produced on the spring for one end of saidtie rod and a second bearing defining a pivot point for the other end ofsaid tie rod being produced on the indicator and the tie rod beingarticulated with both bearings, the spring being subjected to a specificreference pressure while the deflection of said spring is beingmeasured. It is provided in accordance with the invention that thedeflection of the spring is measured before the bearings are producedfor the tie rod and that the geometric locations at which the bearing onthe spring and the second bearing are produced are determined from themeasured deflection on the basis of experimentally ascertained orcalculated associations.

In accordance with a second embodiment of the invention, the citedobject is accomplished by a method for producing a spring manometermeasuring system consisting of an indicator, a spring serving as adeviation detector and a tie rod connecting the indicator to the spring,a bearing defining an end point being produced on the spring for one endof said tie rod and a second bearing defining a pivot point for theother end of said tie rod being produced on the indicator and the tierod being articulated with both bearings, the spring being subjected toa specific reference pressure while the deflection of said spring isbeing measured. It is provided in accordance with the invention that thedeflection of the spring is measured before one of the two bearings isproduced for the tie rod and that the geometrical location at which thisone bearing is produced is determined from the measured deflection onthe basis of experimentally ascertained or calculated associations.Preferably, the second bearing, i.e. the bearing on the indicator, isnot produced until after the deflection of the spring has been measured.

Unlike the first embodiment of the invention, both bearings are notproduced after the spring deflection has been measured in the secondembodiment of the invention, but rather only one of the two bearings isproduced only after the measurement, while the other bearing was alreadyproduced previously in the conventional manner.

Both embodiments of the invention coincide in that at least one of thetwo bearings for the tie rod is produced only after the springdeflection has been measured and that at least the geometric location ofthis one bearing is determined from the measured deflection on the basisof experimentally ascertained or calculated associations.

It is already known from U.S. Pat. No. 3,805,619 to adjust the span in aspring manometer measuring system without an indicator, i.e. with apointer directly connected to the end of a spiral spring, in such amanner that the end of the spring attached to the housing is displacedrelative to the housing of the manometer during adjustment and is thenfixed in position, thereby extending the active length of the spring. Inthe case of the invention, however, the active length of the spring isdefinite. The inventive approach relates to the connection between thefree end of the spring and the indicator. This connection is notaffected in the approach according to U.S. Pat. No. 3,805,619.

As a rule, the nominal pressure serves as the reference pressure. Thereis an advantageous possibility, however, for the reference pressure tobe greater than the nominal pressure. A possibility of production is toperform the measurement after the spring manometer measuring system hasbeen completely assembled except for the tie rod.

In a measuring system comprising an end piece on the spring and asegment lever associated with the indicator, each bearing is drilled orpunched in the end piece or segment lever preferably as a hole, althoughthere are also other possibilities to produce the bearings. Aprefabricated bearing can be secured to the end piece or segment lever,for example. The tie rod is articulated only after at least one bearinghas been produced at the correct location resulting from themeasurement. This inventive approach renders the conventional adjustingprocedure superfluous, since the production of at least one bearing atthe correct location replaces this adjusting operation. It wasrecognized that conventional adjusting was necessary because thebearings were produced before the position of the end point and pivotpoint required for each individual measuring system by virtue of itsproperties and manufacturing dimensions was known so that the bearingshad to be moved to the required position at a later time. In accordancewith the invention, at least one of the bearings is not formed untilafter the required position of the pivot point and the end point or oneof these points has been established for each individual measuringsystem so that the bearing or bearings can be formed at these points anda correction can be omitted. This also applies to the second embodimentof the invention, for example, if the distribution of the end pointposition from spring to spring is low and if only the second bearing isproduced on the indicator on the basis of the result of measurement.

In order to determine the required position of the end and pivot pointsor one of these points from the measurement of the deflection of thespring, the required correlations can initially be derived fromconventionally adjusted measuring systems and can then be compiled inthe form of a table. This table can then be used for setting thedrilling or punching device or the like with which the bearings or thebearing is produced, or to position the measuring system or the springand the indicator in this device. Alternatively, the correlations mayalso be calculated, since the geometric and kinematic relations betweenthe spring deflection or spring excursion, the lever arm, the end pointposition and the pivot angle are known. The results of this calculationcan also be compiled in a table and used as the setting or positioninginstructions. The work to be done is thus reduced to setting the devicefor producing at least one of the bearings to a set value associatedwith the result of measurement or to position the measuring system orthe spring and indicator in accordance with this value. This procedurerequires substantially less time and experience than the adjustment inthe afore-described manner which is now superfluous.

The inventive method according to the two embodiments can be executedespecially advantageously in such a manner that the result ofmeasurement is supplied to a control device which determines from theresult of measurement the set value for the drilling or punching deviceor the like or the required position of the measuring system or thespring and indicator in this position and then regulates the drilling orpunching device or positioning device to the corresponding value. In sodoing, the control device can also control the measuring procedure aswell. This approach makes the completely automatic production of thebearings possible starting from the time of measurement so that time andoperating expenses are reduced.

The inventive approach according to the two embodiments of the inventionalso make it possible to disregard or abandon the deformability of theend piece and/or the segment lever or an elongated hole in the segmentlever or end piece. This simplifies the production thereof and makes itpossible to employ non-metallic materials for the segment lever which,for example, could serve to compensate for errors due to temperature.

In the method according to the first embodiment of the invention bothbearings are preferably produced simultaneously.

In addition to the omission of the adjustment work and the associatedsavings of time and work, the method according to the first embodimentof the invention also achieves other advantages which will be explainedin the following.

Since the bearings are only produced subsequently, greater tolerancescan be allowed when connecting the tube spring to the end piece and tothe deviation detector support.

In an advantageous development of the first embodiment of the invention,it can be provided that the indicator is maintained in a mechanicallydefined end position during the production of the bearings, while at thesame time the spring is subjected to the pressure which is to besuppressed at point zero of the indicator. The result of this approachis that the measuring system has a defined zero position with zerosuppression without requiring a stop pin on the dial or an adjustablestop at any other location. The stop pin can therefore be omitted,thereby simplifying the production of the manometer and reducing thedanger of damaging the dials.

Finally, the method according to the first embodiment of the inventionmakes it possible to insert the tie rod by machine. Since in theconventional approach the positions of the end and pivot points are notknown exactly due to the manufacturing dimensions at the time the tierod is inserted, the tie rod must be inserted manually. In the inventiveapproach, however, the positions of the end and pivot points are knownexactly for each measuring system from the preceding production step,i.e. the production of the bearings, so that the bearings can also bepositioned exactly at defined locations in a device for inserting thetie rod as well, whereupon the tie rod is inserted by means of thisdevice. This also reduces the operational costs considerably.

Another object of the invention is to provide a device for producing aspring manometer measuring system by means of which measuring system canbe produced which require no adjustment.

This object is accomplished in accordance with the invention by a devicefor producing a spring manometer measuring system consisting of anindicator, a spring serving as a deviation detector and a tie rodconnecting the indicator to the spring and also articulating on bearingson the indicator on the one hand and on the end of the spring on theother hand, said device including

(a) a measuring device including a clamping chuck for clamping thespring into position and a pressure medium connection through which thespring can be supplied with a pressure medium,

(b) a measuring means belonging to said measuring device for measuringthe deflection of the spring when subjected to pressure which includes adetector which supplies signals corresponding to the positions of theend of the spring under pressure and not under pressure when there is arelative movement between the detector and the end of said spring,

(c) a device for forming the bearing(s) on the spring and/or on theindicator, and

(d) a control device for controlling the device for forming thebearing(s) in accordance with the signals from the detector.

Both the first embodiment of the inventive method as well as the secondembodiment of the inventive method can be performed by means of thisdevice.

A measuring device comprising a clamping chuck for clamping the springin position and a pressure medium connection through which the springcan be supplied with a pressure medium, is already known per se fromconventional adjustment devices (cf. Rohrbach: "Handbuch furelektrisches Messen mechanischer Grossen" (Handbook for the ElectricalMeasurement of Mechanical Quantities), VDI-Verlag, Duesseldorf, 1967,page 541). The measurement is performed by means of the known measuringdevice by reading off the pressure which is indicated by the measuringsystem which has already been provided with a pointer.

Moreover, devices are also known per se which form a bearing. The knowndevices are punching or drilling devices by means of which holes areformed in individual parts such as the segment lever of an indicator orthe end piece for a spring, for example, before they are assembled withthe indicator or the spring.

It can be provided in an advantageous development of the inventivedevice that the measuring device and the device for forming thebearing(s) are stations in machines through which the measuring systempasses in succession. In addition, a control device is preferablyprovided which controls the measuring device and the device for formingthe bearing(s) and, in so doing, automatically supplies to the devicefor forming the bearing(s) corresponding control signals calculated onthe basis of the measured result. Furthermore, it can be preferablyprovided--to execute the second embodiment of the inventive method--thatthe device for forming the bearings includes two tools, with which twobearings can be formed, and a clamping chuck for clamping a measuringsystem into position which consists of the spring, a deviation detectorsupport and an indicator. It is also preferably provided that theclamping chuck and the tools are adapted to be turned and set. This alsofacilitates a correction of errors in linearity in the spring or theindicator. In accordance with the invention, the locations of thebearings are determined on the basis of the spring deflection. This,however, does not exclude the fact that in addition other quantities canalso be taken into account when the locations of the bearings aredetermined. If only the spring deflection is measured, however, only theinfluence of the spring deflection, which varies from spring to spring,on the span and linearity will be corrected. This is sufficient forpractical purposes. If there are clear differences in the linearitybehaviour of the springs from one batch of springs to another, thesedifferences can also be taken into account by appropriate turning andresetting the clamping chuck, for example, in the device for forming thebearings. Moreover, it can also be provided that the relative positionof the clamping chuck and the tools is also set depending on therespective measurement of the spring deflection.

Finally, yet another object of the invention is to design a tube springmanometer in such a manner that production and adjustment of themanometer become less expensive without reducing the display accuracy ofthe manometer.

This object is accomplished in accordance with the invention by a tubespring manometer comprising a deviation detector support, a tube springrigidly connected at one end with the deviation detector support and atthe other end with an end piece, a pointer train including a toothedsegment to which a segment lever pivotally mounted on a segment axisbelongs, and further comprising a tie rod which is rigid at least in thelongitudinal direction, whose length is invariable and which articulatesat the bearings both with the segment lever arm located on one side ofthe segment axis as well as with the end piece, circular holes beingformed in the segment lever arm and in the end piece at the bearings. Itis provided that the segment lever arm is a massive, plate-like elementin the area between the segment axis and the bearing hole and that theend piece includes a plate-like element whose greatest dimensions lie ina plane common to the segment lever arm.

The inventive manometer thus features a "novel kinematics", i.e. a noveldevelopment of the combination of end piece, tie rod and segment leverarm which connect the end of the spring with the pointer train. Thespecial feature of this new kinematics is to be seen in the plate-likeor laminar design of the end piece and the segment lever arm as well asin the construction of all three kinematic elements, the end piece, thetie rod and the segment lever arm which is termed rigid, i.e. invariablein length.

The non-use of hooks, elongated holes and other possibilities of varyingthe spacing between the segment axis and the pivot point, the pivotpoint and end point as well as the end point and end of the springsimplifies the production of the kinematic elements. This omissionbecomes possible due to the plate-like or laminar design of the segmentlever arm and end piece, since adequate material and sufficiently largesurfaces exist in the area between the end point and the pivot point tobe able to produce the holes for the end and pivot points on theassembled measuring system comprising the deviation detector support,tube spring and pointer train after assembly has been completed. Theposition of the holes is determined from the properties of therespective measuring system, especially the spring deflection undernominal pressure, in such a manner that the span, i.e. the pointerdeflection under nominal pressure, and the linearity of the display arewithin permissible tolerance fields. The inventive manometer is thusadjusted in spite of the structurally simple kinematics withoutrequiring a conventional adjustment by subsequently changing theposition of the pivot point and end point or the length of the tie rodso that, on the one hand, the production of the kinematic elements isless expensive and, on the other hand, the adjustment work can beomitted.

The end piece is preferably connected in the common plane to the end ofthe tube spring and is stiffened to prevent bending. Especially simpleproduction of the segment lever arm results from the fact that thesegment lever arm is bordered on the side by two rectilinear edges.

The novel kinematics can be developed further in an advantageous fashionin that the tie rod is a plastic member which has two tabs which can besnapped into the holes in the end piece and in the segment lever arm.

A special advantage of the novel kinematics can be seen in the fact thatit makes it possible to provide a non-adjustable zero stop pin in thepointer train or on the deviation detector support for a pivotal memberof the pointer train. This stop replaces, for example, a stop pin on thedial of the manometer which increases the production costs in the caseof conventional manometers and also is accompanied by the danger that itwill damage other dials during storage. In accordance with theinvention, for example, a stud bolt of the pointer train forms the zerostop pin, against which the toothed segment or the segment lever abut inthe zero position. This is made possible by the inventive design of thekinematics which allows the bearings for the pivot point and the endpoint of one of these bearings to be produced while the segment lever,for example, abuts against the stud bolt and the tube spring issubjected to that pressure which is associated with the zero position ofthe pointer. A non-adjustable stop in the pointer train is impossible inconventional manometers, since the position of its movable parts must bevariable in order to effect adjustment.

Other advantageous designs and further developments of the invention arerevealed in the patent claims.

The invention will be explained in the following with reference to atube spring manometer.

In the drawings,

FIG. 1 is an elevation of one embodiment of a spring manometer measuringsystem in accordance with the invention;

FIG. 2 is a schematic illustration of an inventive device for producinga spring manometer measuring system;

FIG. 3 is a partial illustration of a pointer train;

FIG. 4 is a schematic illustration of another inventive device forproducing a spring manometer measuring system.

FIG. 1 illustrates an embodiment of a measuring system 8 of a tubespring manometer. The housing, the dial and the pointer of saidmanometer are not shown.

The measuring system includes a deviation detector support 12 to which atube spring 10 is welded at one end. A bore 14 (see FIG. 2) extendsthrough said deviation detector support 12 and communicates with theinterior of the tube spring 10. Furthermore, the measuring systemincludes a pointer train 20 comprising a pointer shaft pinion 22 and atoothed segment 24 which engages said pointer shaft pinion. The toothedsegment 24 has a segment lever 26 which is pivotally mounted on asegment axis S. The segment lever arm 31 is formed by that portion ofthe segment lever which is located on the side of the segment axisfacing away from the pointer shaft pinion 22.

An end piece 16 is secured to the free, closed end of the tube spring10, for example by welding. A circular hole 18, which is evident in FIG.2, is located in the end piece, serves as a bearing for a tie rod 30 anddefines the end point E. A circular hole 28 (see FIG. 2) is also locatedin the segment lever arm 31, serves as a bearing and defines the pivotalpoint A. Shoulder rivets are secured in these holes on which the tie rod30 articulates, thereby transmitting the deflection of the end of thetube spring under pressure to the pointer train 20. The tie rod,together with the end piece 16 and the segment lever 26, thus form thekinematics of the manometer. It goes without saying that the tie rod canbe mounted in another manner other than by means of shoulder rivets. Forinstance, the tie rod can be a plastic part with two tabs which aresnapped into the holes in the segment lever arm and the end piece.

The kinematics of the manometer is stiff as evident from FIG. 1. Neitherthe segment lever arm 31 nor the tie rod 30 nor the end piece 16 permita change in length between the segment axis S and the pivotal point A orthe pivotal point A and the end point E or the end point E and the endof the spring.

The segment lever arm 31 is a flat, plate-like element which islaterally defined by rectilinear edges and which has no cuts or the likeand no hook-like design adjacent the straight line extending from thesegment axis to the pivotal point. The surface of the segment lever armwhich is visible in the top elevation in accordance with FIG. 1 is solarge that the hole 28 for the pivotal point A was able to be made at asuitable location within sufficiently wide limits.

The end piece 16 is also a flat, plate-shaped element which is locatedin the same plane as the segment lever arm 31. The end piece 16, likethe segment lever arm, has such a large surface area in this plane thatthe hole for the end point E was able to be made at a suitable locationwithin sufficiently wide limits.

FIG. 3 schematically illustrates the pointer train 20 in the positionwhich it assumes at zero and when the hole 28 (see FIG. 2) is beingmade.

A stud bolt 27 of the pointer train serves as a stop against which thesegment lever 26 abuts. This stop can also be formed by the deviationdetector support 12, e.g. the edge thereof, as is shown in FIG. 1.

FIG. 1 also shows the spring excursion F, viz. the deflection of the endof the spring at nominal pressure, the lever arm L, viz. the distancebetween pivotal point A and segment axis S, the position of the endpoint E as the distance P of the end point from the imaginary fulcrum Dof the spring end and the pivot angle α between the straight line AS andthe straight line AE.

The deflection of the end of the spring is converted by theafore-described measuring system into a rotation of the pointer shaftpinion. In so doing, the span, i.e. the pointer deflection at nominalpressure, is influenced by the spring excursion F, the end pointposition and the lever arm L. The linearity is influenced substantiallyby the pivot angle α. The geometrical and kinematical relations betweenthe spring excursion F, the end point position, the lever arm L and thepivot angle α are known and can be derived from FIG. 1.

In the case of conventional manufacture, the position of the end point Eand the pivotal point A must be adjusted to the spring excursion F. Itis evident, for example, that an increase in the lever arm L which ismade to compensate for too much spring excursion F will change the pivotangle and thus the linearity. If the distance P is varied to correct thelinearity, i.e. varying the pivot angle α, the span will vary as well sothat the position of the pivotal point A must be changed anew. Thiscomplicated operation is not necessary in the inventive concept, sincethe end point E and the pivotal point A or at least one of these pointsare made at locations correctly associated with the spring excursion Fso that the end piece 16 and the segment lever 26 can have the designs,for example, which are illustrated in FIG. 1 and which do not have tooffer the possibility of a subsequent change in the position of the endpoint E and the pivotal point A by bending or shifting.

An embodiment of the inventive device is illustrated in FIG. 2. Thedevice illustrated in FIG. 2 is suitable for executing the firstembodiment of the inventive method. The device includes a measuringdevice 32 and a device for forming bearings which is designed as adrilling device 34 in the illustrated embodiment. Furthermore, thedevice also comprises a control device 36.

The measuring device includes a clamping chuck 40 which is supported bya carriage 42. The carriage is guided by a carriage guide 44 and can bemoved by a stepping motor 48 via a spindle 46. A tube spring 10 isclamped into position in the clamping chuck 40 on the deviation detectorsupport 12 in the illustrated embodiment which is already connected tothe pointer train 20 as well.

The measuring device 32 also includes a pressure connection which isformed by an air nozzle 50. The tip of the nozzle can be pressed intothe aperture of the bore 14 so that the compressed air from the airnozzle 50 acts directly on the tube spring 10. The air nozzle 50 isdisplaceably guided in such a manner that it can follow the displacementof the deviation detector support 12 by the carriage.

The measuring means 52 of the measuring device is formed by aspring-loaded sensor 54 and a touch switch 56. The slight springpre-bias which is exerted on the sensor keeps this away from the touchswitch. One arm of the sensor rests on the end of the spring at aspecific distance in front of the end piece 16.

The drilling device 34 includes two drilling tools 58 and 59. Thedistance between the centers of these tools is equal to the distancebetween the bores or the like of the tie rod 30 which form the bearings.This distance is constant in the illustrated embodiment, but can also beadjustable in order to be adapted to other tie rod lengths. Furthermore,the drilling device also includes a clamping chuck 60 positioned on acarriage 62 which can be moved on a carriage guide 64 by a steppingmotor 68 via a spindle 66. The carriage guide is attached to a plate 70which can be pivoted about the axis of the drilling tool 59 located onthe right in FIG. 2. The entire drilling device 34 is equipped so thatwhen the carriage 62 is moved, the segment axis S moves along a straightline connecting the axis of the right drilling tool 59 and the segmentaxis S.

It is stated above that the clamping chuck 62 can be moved. It is alsopossible to keep the chuck stationary and to move the drilling toolsaccordingly. Likewise, the drilling tools can be pivoted about the axisof the drilling tool 59 instead of the clamping chuck being pivotal bymeans of the plate 70.

Moreover, the drilling device has a detector (not shown) which generatesa control signal when the segment axis S is positioned on the axis ofthe drilling tool 59.

The control device 36 is connected with the touch switch 56, the sourceof the pressurized medium, the stepping motor 48, the drilling tools andthe stepping motor 68 through signal leads 72, 74, 76, 78 and 80. It isalso connected with the detector (not shown) of the drilling device. Thecontrol device includes a counting circuit 82 and a control circuit 84.

The mode of function of the described device is explained in thefollowing.

The deviation detector support 12 is first of all clamped into positionin the clamping chuck 40. The tube spring 10 with its end piece 16 andthe pointer train 20 with its segment lever 26 are located on thedeviation detector support. A bearing for the tie rod is providedneither in the end piece 16 nor in the segment lever.

Controlled by the control device, the air nozzle 50 is then movedagainst the open end of the bore 14. This state is illustrated in theleft half of FIG. 2. The stepping motor 48 is energized thereafterthrough the signal lead 76 so as to cause the carriage 42 to move to theright in FIG. 2. In doing so, the end piece 16 is thrust against thesensor 54, thereupon actuating the touch switch 56. This supplies afirst measuring signal to the control device 36 through the signal lead72. The source of pressure medium is then activated through the signallead 74 in such a manner that the tube spring 10 is subjected to thenominal pressure. The end of the spring or the end piece 16 is therebydeflected (to the left in FIG. 2) so that it is lifted away from thesensor 54, enabling this to release the touch switch 56.

The stepping motor 48 is again supplied with switching pulses throughthe signal lead 76 and continues to move the carriage 42 farther to theright (in FIG. 2) until the end piece 16 again actuates the touch switch56 via the sensor 54. This produces a second measuring signal in thesignal lead 72. The switching pulses supplied to the stepping motor 48between the two measuring signals are counted and indicated by thecounting circuit 82. This indication is a measure of the springexcursion F.

The measuring system 8 is thereafter removed from the measuring device32 and placed in the clamping chuck 60 of the drilling device 34, thesegment lever 26 being maintained in a defined position in the drillingdevice. The optimally predetermined pivot angle α is set on the drillingdevice by rotating the chuck 60 or the plate 70. This pivot angle has tobe adjusted subsequently from batch to batch, but can also be set frommeasuring system to measuring system which would require an additionalsetting device for the drilling device.

A table, for example, whose compilation has already been explained,reveals a set value associated with the measured value which is ameasure of the required lever arm L. This set value already takes anoptimally predetermined pivot angle α into account together with thefact that giving the pivot angle with the lever arm also changes theposition of the end point. The number of pulses required by the steppingmotor 68 to move the carriage 60 a distance corresponding to therequired lever arm L can serve as the set value. This set value is infedto the control device 36 and is stored in a control dircuit 84. Thestepping motor 68 is thereafter supplied with switching pulses throughthe signal lead 80 in such a way that the carriage 62 is moved to thedrilling tools 58 and 59. When the detector (not shown) determines thatthe segment axis is positioned under the drilling tool 59, the directionof rotation of the stepping motor 68 is reversed and the stepping motor68 is then supplied with switching pulses, the number of whichcorresponds to the stored set value. As soon as this number has beenattained, the drilling operation by means of the drilling tools 58 and59 is actuated through the signal lead 78. These drilling tools drillthe holes 18 and 28, after which the carriage 62 together with themeasuring system 8 is moved to the position illustrated in the righthalf of FIG. 2 in which the measuring system can be removed.

The drilled holes 18 and 28 are spaced in accordance with the tie rod,they form together with the segment axis S the desired pivot angle α andassume the position required for the measured spring excursion withrespect to the lever arm L and the distance P.

The defined position in which the segment lever 26 is maintained in thepunching device can be determined, for instance, by causing the segmentlever to abut on a stud bolt 27 (see FIG. 3).

In a further development of the invention the drilling device 34according to FIG. 2 also possesses an air nozzle (not shown) which issimilar to the air nozzle 50 and through which the tube spring issubjected during drilling to the pressure which must be suppressed atzero. If the segment lever 26 simultaneously abuts on the stud bolt 27or the like, the holes 18 and 28 will be drilled such that the measuringsystem suppresses the pressure applied to the tube spring duringdrilling after the tie rod has been inserted, since the segment levercannot assume a position corresponding to lower pressures because italready abuts against the stud bolt at this pressure. This makes a stoppin on the dial superfluous.

The control device 36 can also be designed in a different way than theconstruction described above. It can have process and functionalcomputing properties, for example, and can operate in such a manner thatit controls not only the work cycles of the measuring and drillingdevices or the like in a correct timed sequence, but also automaticallyassociates the measured result and the set value, for instance, bycalculations based on the geometric relationships of the measuringsystem.

Furthermore, the device according to FIG. 2 can be supplemented by ameans for inserting the tie rod. This insertion means (not shown) isdisposed downstream of the drilling device 34 or the like and has, forexample, substantially the same construction and the same mode offunction as the drilling device, the sole difference being that thedrilling tools 58 and 59 are replaced by an insertion tool whichsupports the tie rod or a tie rod with associated rivets and inserts itinto the holes 18 and 28 from above (in FIG. 2) while simultaneouslyattached said tie rod to the segment lever and the end piece in anarticulated way. The insertion means is controlled in the same way andwith the same set value as is the case with the drilling device.

Yet another embodiment of the inventive device is illustrated in FIG. 4.The device illustrated in FIG. 4 is especially suitable for executingthe second embodiment of the inventive method. The device shown in FIG.4 coincides essentially with the device illustrated in FIG. 2. Identicalparts and identical elements of both devices have been designated by thesame reference numerals in FIGS. 2 and 4. Only the differences in thedevice according to FIG. 4 as compared to the device according to FIG. 2will be explained in the following.

The drilling device 34 has only one drilling tool 59 in the deviceaccording to FIG. 4. The drilling device 34 is arranged so that thesegment axis S moves along a straight line connecting the axis of thedrilling tool 59 with the segment axis S when the carriage 62 is moved.The carriage guide 64 can be pivoted about the axis of the drilling tool59 in the plane of the drawing in FIG. 4.

The device shown in FIG. 4 is suitable, for example, for producing thebearing on the segment lever, i.e. the hole 28, in the case of a springmanometer measuring system already provided with the bearing or the hole18 in the end piece 16 as shown in the left half of FIG. 4. Thedeflection of the tube spring 10 is measured as was explained withreference to FIG. 2. The measuring system 8 is thereafter removed fromthe measuring device 32 and inserted in the clamping chuck 60 of thedrilling device 34, the segment lever 26 being held in a definedposition in the drilling device which is then set to such an angle β byturning the chuck 60 or the plate 70 that the most favourable pivotangle α results on the average. The angle β only needs to be adjustedsubsequently from batch to batch.

A table, for example, whose compilation has already been explained,reveals a set value associated with the measured value which is ameasure of the required lever arm L. This set value already takes anoptimally predetermined average pivot angle α into account. The numberof pulses required by the stepping motor 68 to move the carriage 62 adistance corresponding to the required lever arm L can serve as the setvalue. This set value is supplied to the control device 36 and is storedin a control circuit 84.

The stepping motor 68 is thereafter supplied with switching pulsesthrough the signal lead 80 in such a way that the carriage 62 is movedto the drilling tool 59. When the detector (not shown) determines thatthe segment axis is positioned under the drilling tool 59, the directionof rotation of the stepping motor 68 is reversed and the stepping motor68 is then supplied with switching pulses whose number corresponds tothe stored set value. As soon as this number has been attained thedrilling operation by means of the drilling tool 59 is actuated throughthe signal lead 78. The drilling tool drills the hole 28, after whichthe carriage 62 together with the measuring system 8 is moved to theposition illustrated in the right half of FIG. 4 in which the measuringsystem can be removed.

The drilled holes 18 and 28 form together with the segment axis S thedesired pivot angle α on the average and take up the position requiredfor the measured spring excursion with respect to the lever arm L andthe distance P.

It goes without saying that numerous modifications of the describeddevice are possible within the scope of the invention, such as designingthe measuring device and the drilling device or the like and even, ifdesired, the insertion means as stations of a swivel table machine inwhich each measuring system is successively clamped in the same chuck,whereupon they pass through the individual stations.

We claim:
 1. A device for producing a spring manometer measuring systemconsisting of an indicator, a spring serving as a deviation detector anda tie rod connecting the indicator to the spring and also articulatingon bearings on the indicator on the one hand and on the end of thespring on the other hand, comprising(a) a measuring device including aclamping chuck for clamping said spring into position and a pressuremedium connection through which the spring can be supplied with apressure medium, (b) a measuring means belonging to said measuringdevice for measuring the deflection of said spring when subjected topressure which includes a detector which supplies signals correspondingto the positions of the end of the spring under pressure and not underpressure when there is a relative movement between the detector and theend of said spring, (c) a device for forming one of said bearings on thespring and on the indicator, and (d) a control device for controllingsaid forming device for forming the bearings in accordance with thesignals from the detector.
 2. A device according to claim 1, whereinsaid detector is a sensor which can be brought into contact with the endof the spring by relative movement between the sensor and spring, andthe relative movement between the points of contact with and withoutpressure exerted on the spring serves as a measure of the deflection ofsaid spring.
 3. A device according to claim 1, wherein a display devicedisplays the results of measurement.
 4. A device according to claim 1,wherein the device for forming the bearings is a drilling or punchingdevice.
 5. A device according to claim 1, wherein the device for formingthe bearings is a device for affixing or welding pre-fabricatedbearings.
 6. A device according to claim 1, wherein the device forforming the bearings includes two tools with which two bearings can beformed, and said clamping chuck clamps said measuring system intoposition and consists of said spring, a deviation detector support andsaid indicator.
 7. A device according to claim 6, wherein the spacingbetween the two tools is adapted for a predetermined setting.
 8. Adevice according to claim 6, wherein said chuck can be moved relative tothe tools in a plane of the measuring system.
 9. A device according toclaim 8, wherein a stepping motor produces the relative movement betweensaid clamping chuck and the tools.
 10. A device according to claim 8,wherein said detector can detect the position of a segment axis of saidindicator.
 11. A device according to claim 10, wherein said controldevice includes a control circuit which is connected to the detector todetect the position of said segment axis of said indicator and whichcontrols the relative movement of said clamping chuck and the tools inthe device for forming the bearings such that the distance between thesegment axis and the point of application of the tool on a segment levercorresponds to a value supplied to the control circuit.
 12. A deviceaccording to claim 6, wherein said clamping chuck and the tools areadapted to be pivoted and adjusted relative to one another in a plane ofthe measuring system.
 13. A device according to claim 12, wherein saidclamping chuck is adapted to be rotated about the axis of the tool whichproduces a point of articulation on a segment lever.
 14. A deviceaccording to claim 6, wherein said device for forming said bearingsincludes a pressure connection through which said spring can be suppliedwith a pressure medium, and a positioning means which permits a segmentlever of said indicator to press against a stop of said indicator.
 15. Adevice according to claim 1, wherein said control device serves tocontrol said forming device and to control said measuring device.
 16. Adevice according to claim 1, wherein said control device continuouslydetermines a value to be supplied to a control circuit from signals fromsaid detector and supplies this value to said control circuit.
 17. Adevice according to claim 1, wherein said measuring device and saidforming device are stations in a machine which said measuring systempasses through in succession.
 18. A device according to claim 17,wherein said tie rod is inserted into said measuring system.